1. Field of the Invention
This invention relates primarily to gravure printing, but also applies to gravure offset and flexography printing and more particularly, to a method and apparatus for compensating for imperfect cylinders and machinery for layer-to-layer printing such that uniform material deposition and/or minimized subsequent over-lays of deposition occur.
2. Description of the Related Art
Traditionally gravure prints are judged visually. Both the sensitivity and the limitations of the human eye define the press tolerances. The printed electronic market operates on a functional electronic basis, not the former visual basis, and therefore is driven by a different set of criteria.
The visual requirement for layer-to-layer registration accuracy for traditional printing is approximately 75 microns, improving this to a smaller tolerance yields no perceived value. However, electronic devices and printed circuits are sensitive to several orders of magnitude less than the human eye. Hence registration requirements and systems for printed electronics must be much more precise.
These higher precision requirements tend to dramatically increase costs.
U.S. Pat. No. 5,329,215 is an approach for correcting errors associated with leadscrews used during engraving of a circuit Error Mapping.
U.S. Pat. No. 7,661,358 discloses an apparatus and method for forming a predetermined pattern on a substrate using a gravure offset printing method. The apparatus for forming a pattern using a gravure offset printing method comprises a gravure on which a pattern to be filled with a color resist is formed; a roller brought into contact with the gravure to transfer the pattern formed on the gravure to the roller and then to print the transferred pattern onto a substrate; a roller driving means for rotating and horizontally driving the roller to transfer the pattern formed on the gravure to the roller and then to print the transferred pattern onto the substrate as it is; and a substrate support on which the substrate is placed. Further, the roller driving means includes a rotational driving unit for rotationally driving the roller; a horizontal driving unit for horizontally driving the roller independently of the rotational driving unit; and a control unit for controlling driving speeds of the rotational and horizontal driving units. The device in contrast attempts to transfer the cylinder with pattern to the substrate with complete fidelity to the original cylinder.